1. Field of the Invention
This invention relates to a process and apparatus for multi-stage absorption/adsorption and desorption of a process gas using a multiple concentric tube apparatus wherein a thermal wave passing through a high temperature salt in the process of desorption is directly utilized together with the heat of absorption/adsorption for desorption of absorbed/adsorbed process gas in a direct thermally coupled low temperature salt. The process and apparatus is particularly useful in air conditioning applications.
2. Description of Related Art
Triple tube heat exchangers for transfer of heat to or from a plurality of fluids which flow through the heat exchanger in helical directions through a series of fins, which in combination with the walls, conduct heat from the warmer fluid to the cooler fluid which absorbs the heat and carries it away is known from U.S. Pat. No. 2,703,701.
Annular chemical reactors for exothermic reactions having a central rotatable drum cooled on the inside and having extensions on the outer surface extending into an annular reaction volume defined by an annular outer cooling jacket are taught by U.S. Pat. No. 3,438,742.
Phase change chemical thermal energy storage is known: U.S. Pat. No. 3,960,207 teaches a stacked plurality of ring-like disc shaped containers holding a phase change thermal energy storage material with a thermal exchange fluid passing through the conduit formed by the center of the rings. U.S. Pat. No. 4,250,958 teaches a plastic double tube structure having integral spaced webs between the tubes forming segments which are filled with a phase change thermal energy storage material, the inner tube forming a conduit for passage of a heat transfer fluid.
Use of a shell and tube reactor in the catalytic formation of ammonia with a plurality of catalyst beds arranged to preheat reactants by indirect heat exchange with effluen from the first catalyst bed and subsequent cooled gas flow to the second catalyst bed is taught by U.S. Pat. No. 4,452,760. Multiple shell and tube interchangers for cooling reaction gas streams leaving multi-catalytic beds in an ammonia synthesis converter by thermal exchange with incoming feed gases are taught by U.S. Pat. No. 4,696,799.
Sorption and desorption of gaseous refrigerants in a liquid which is then slurried with a particulate solid to form a ligand complex with the heat of the complex-forming reaction being transferred for recovery to heat exchange surfaces at different elevations is taught be U.S. Pat. Nos. 4,822,391 and 4,875,915.
U.S. Pat. No. 4,848,994 teaches a heat exchange system using the cooling created by specific metal salt/ammonia ligand complex compounds which are alternately heated and cooled to alternately desorb and adsorb, respectively, providing energy storage or refrigeration.
Constant pressure staging of a plurality of solid reactant adsorbents of different gaseous reactant vapor pressures wherein heat transfer fluid at one temperature desorbs gases in endothermic reactions and then at a lower temperature adsorbs gases in exothermic reactions with a portion of the heat released during exothermic reactions or a portion of the heat adsorbed during endothermic reaction passed by the heat transfer fluid to a heat exchanger for energy recovery is taught by U.S. Pat. No. 5,025,635. The process and apparatus of the U.S. Pat. No. 5,025,635 patent, based upon circulation of a heat transfer fluid, is suitable for heat actuated heat pumps, thermal compressors and heat pumps activated by mechanical work or pressure.
Discrete constant pressure staging of solid-vapor compound reactors wherein a plurality of solid sorbents each having a different sorption and desorption temperature is each located in a different chamber of a reactor, or in separate reactors, with the exothermic heat of sorption from one chamber being transferred by a heat exchange fluid for use in endothermic desorption in another chamber is taught by U.S. Pat. No. 5,079,928. The process and apparatus taught by the U.S. Pat. No. 5,079,928 patent, based upon circulation of a heat transfer fluid, is useful as heat actuated heat pumps, thermal compressors and heat pumps activated by mechanical work or pressure.